What you need to know - Wednesday 12/15/10

Zipcar raises $21M; RiseSmart raises $3M; Yahoo lays off 4% of staff

Zipcar, a car-sharing service announced that it has raised $21 million. This is the series g round of funding, which was led by Meritech Capital Partners. Meritech gave $20 million of the funding. The rest came from Pinnacle Ventures.

The CEO and founder of Facebook CEO was named Time Magazine’s person of the year. Mark Zuckerberg will be on the cover of the magazines special edition.

Truphone, an international roaming and app company for mobile devices, is rebranding as “Tru”. No word on weither or not the company will migrate to Tru.com or remain at its current URL.

DeNA, the biggest mobile social-gaming platform in Japan, will have one of its social game platforms, called Mobage, carried on Samsung's Android-based smartphones. This update applies to phones sold outside Japan.

Twitter has launched an updated guide for businesses that are interested in making the micro-sharing service. The guide will include both posting and advertising information.

Sega has announced that it will be developing a social game themed around its Yakuza games. The project will most likely run on Gree, a social network available in Japan for mobile users.

Gmail now supports full email delegation. This feature will let another Google account holder access your email account and respond to them. Access to this feature can be found in the Gmail settings.

Yahoo has confirmed that it will be letting go roughly 4% of its global workforce, which is about 560 employees. These layoffs come just two weeks before Christmas.

RiseSmart, an outplacement and recruitment process outsourcing solutions company, announced Tuesday that it has raised $3 million. The round included Norwest Venture Partners, Storm Ventures and other angel investors.